1. Field of the Invention
The present invention relates to molded bodies of vulcanized rubber and more particularly refers to a new and improved method of manufacturing a molded body of vulcanized rubber with a firmly adhering layer of varnish, and to the vulcanized varnish coated molded body produced thereby.
2. Description of the Prior Art
Varnishing rubber presents considerable practical difficulties because the surface of the substrate to be varnished is usually apolar and the adhesion due to this is poor. Thus, there have been attempts to overcome these adhesion problems by a pretreatment of the surface to be varnished, for instance, by means of an oxidant or through the use of UV-irradiation (Netherlands Published Non-Prosecuted Application No. 7506793). According to German Published Non-Prosecuted Application No. 28 23 350, an attempt was made to overcome the adhesion problems by using special polyurethane varnishes. Also with the method according to this publication, the varnish is applied after the vulcanizing, so that the method according to this publication did not and could not solve the adhesion problems.